WHY TWO KINDS OF NESTLINGS? 129 
inherited and kept from dying or acquiring more 
down by the extra care of the mother in sitting over 
them. 
Recently some new terms, as substitutes for pre- 
cocial and altricial have been proposed, which in their 
translations are more expressive of the real facts than 
the old terms. The first are called Wedifuge, or 
nest fleers, and the second Vidicolw, or nest stayers 
or nest inhabitants. But in further discussion we 
shall use the old adjectives. 
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